Red-necked Keelback - Rhabdophis subminiatus.
Juveniles are particularly attractive with their bright colours and large eyes.
Here two juveniles keep each other company......but this is anthropomorphize them (to attribute human form or personality to things not human) as they are solitary creatures, only coming together to mate.
This snake is almost unique among snakes and animals as it is both venomous (with a deadly bite) and poisonous (as it can secrete the poison from the toads it eats from a groove in its neck). Nonetheless this snake is essentially harmless to the population in Hong Kong, as it is rear fanged, is not aggressive and very rarely bites, even in defense.